Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a security flaw in the discourse-policy plugin which allowed a user with policy creation permission to gain membership access to any private/restricted groups. Once membership to a private/restricted group has been obtained, the user will be able to read private topics that only the group has access to. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a workaround, review all policies for the use of add-users-to-group and temporarily remove the attribute from the policy. Alternatively, disable the discourse-policy plugin by disabling the policy_enabled site setting.
{
"cwe_ids": [
"CWE-863"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/28xxx/CVE-2026-28282.json"
}{
"cpe": [
"cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*",
"cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest:*:*:*"
],
"extracted_events": [
{
"introduced": "2026.1.0"
},
{
"fixed": "2026.1.2"
},
{
"introduced": "2026.2.0"
},
{
"fixed": "2026.2.1"
},
{
"introduced": "2026.3.0"
},
{
"last_affected": "2026.3.0"
}
],
"source": [
"CPE_RANGE",
"CPE_STRING",
"REFERENCES"
]
}